The present invention relates to a vessel according to the pre-characterizing part of claim 1.
Such a vessel is generally known and is used, inter alia, for the treatment of food products such as, for example: wheat, rice, herbs, nuts, coffee etc. For example, grain is steam-treated in order to soften it, so that it can be used as the unground kernel in the production of wholemeal bread. Or, for example, for the treatment of coffee with supercritical carbon dioxide in order to make it low in caffeine.
GB-A-1 024 824 discloses a vessel according to the pre-characterizing part of claim 1 in which the sieve means comprise strainers to prevent entrainment of granular material by the fluid out of the vessel.
The above vessel however presents a number of disadvantages. Said strainers possess a relatively small surface area, which will undoubtfully give rise to some blocking of the fluid discharge means. A granular material being treated with a liquid will always become more or less tacky and will stick to any surface encountered. Further no sieve means are provided between the fluid feed means and product discharge means.